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            <h2 class="title" style="clear: both"><a id="changedpragmas"></a>Changed PRAGMAs</h2>
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        <dl>
          <dt>
            <span class="sect2">
              <a href="changedpragmas.html#auto_vacuum">PRAGMA auto_vacuum</a>
            </span>
          </dt>
          <dt>
            <span class="sect2">
              <a href="changedpragmas.html#cache_size">PRAGMA cache_size</a>
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          <dt>
            <span class="sect2">
              <a href="changedpragmas.html#incremental_vacuum">PRAGMA incremental_vacuum</a>
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            <span class="sect2">
              <a href="changedpragmas.html#journal_size_limit">PRAGMA journal_size_limit</a>
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      <p>
                The following PRAGMAs are available in the BDB SQL interface, but they
                behave differently in some way from standard SQLite.
            </p>
      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="auto_vacuum"></a>PRAGMA auto_vacuum</h3>
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        <p>
                    The syntax for this PRAGMA is:
                </p>
        <pre class="programlisting">PRAGMA auto_vacuum
PRAGMA auto_vacuum = 0 | NONE | 1 | FULL | 2 | INCREMENTAL </pre>
        <p>
                    Standard SQLite does not allow you to enable or
                    disable auto-vacuum after a table has been created.
                    Berkeley DB, however, allows you to change this at any time.
                </p>
        <p>
                    In the previous syntax, <code class="literal">0</code> and
                    <code class="literal">NONE</code> both turn off auto vacuuming.
                </p>
        <p>
                    <code class="literal">1</code> or <code class="literal">FULL</code> causes
                    full vacuuming to occur. That is, the BDB SQL interface will vacuum
                    the entire database at each commit using a very low
                    fill percentage (1%) in order to return emptied pages
                    to the file system. Because Berkeley DB allows you to call
                    this PRAGMA at any time, it is recommended that you do
                    not turn on FULL vacuuming because doing so can result
                    in a great deal of overhead to your transaction
                    commits.
                </p>
        <p>
                    If <code class="literal">2</code> or <code class="literal">INCREMENTAL</code>
                    is used, then incremental vacuuming is enabled. The
                    amount of vacuuming that is performed for incremental
                    vacuum is controlled using the following PRAGMAs:
                </p>
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            <td>
              <a class="xref" href="addedpragmas.html#bdbsql_vacuum_fillpercent" title="PRAGMA bdbsql_vacuum_fillpercent">PRAGMA bdbsql_vacuum_fillpercent</a>
            </td>
          </tr>
          <tr>
            <td>
              <a class="xref" href="addedpragmas.html#bdbsql_vacuum_pages" title="PRAGMA bdbsql_vacuum_pages">PRAGMA bdbsql_vacuum_pages</a>
            </td>
          </tr>
        </table>
        <p>
                    Note that you can call 
                    <a class="xref" href="changedpragmas.html#incremental_vacuum" title="PRAGMA incremental_vacuum">PRAGMA incremental_vacuum</a>
                    to perform an incremental vacuum operation on demand.
                </p>
        <p>
                    When performing vacuum operations, Berkeley DB
                    defragments and repacks individual database pages,
                    while SQLite only truncates the freelist pages from
                    the database file.
                </p>
        <p>
                    For more information on auto vacuum, see
                    <a class="ulink" href="http://www.sqlite.org/pragma.html#pragma_auto_vacuum" target="_top">PRAGMA auto_vacuum</a>
                    in the SQLite documentation.
                </p>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="cache_size"></a>PRAGMA cache_size</h3>
            </div>
          </div>
        </div>
        <p>
                    BDB SQL has a different default cache size than SQLite. There is a
                    default value increase of PRAGMA cache size for SQL database from
                    2000 pages to 5000 pages.
                 </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="incremental_vacuum"></a>PRAGMA incremental_vacuum</h3>
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          </div>
        </div>
        <p>
                    Performs incremental vacuum operations on demand. You can cause
                    incremental vacuum operations to be performed automatically using 
                    <a class="xref" href="changedpragmas.html#auto_vacuum" title="PRAGMA auto_vacuum">PRAGMA auto_vacuum</a>.
                </p>
        <p>
                    Note that for SQLite, this PRAGMA is used to specify
                    the maximum number of pages to be freed during
                    vacuuming. For Berkeley DB, you use 
                    <code class="literal">PRAGMA bdbsql_vacuum_pages</code> instead.
                </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="journal_size_limit"></a>PRAGMA journal_size_limit</h3>
            </div>
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        <p>
                    For standard SQLite, this pragma identifies the
                    maximum size that the journal file is allowed to be.
                </p>
        <p>
                    Berkeley DB uses multiple journal files, Berkeley DB journal
                    files are different to a SQLite journal file in that they
                    contain information about multiple transactions, rather
                    than a single transaction (similar to the SQLite WAL
                    journal file). Over the course
                    of the database's lifetime, Berkeley DB will probably create
                    multiple journal files. A new journal file is created when
                    the current journal file has reached the maximum size
                    configured using the journal_size_limit pragma.
                </p>
        <p>
                    Note that a BDB SQL interface journal file is referred to as a log
                    file in the Berkeley DB documentation.
                </p>
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